β-FeOOH (akaganeite) in the form of needles, stars, and X- and Y-shaped particles was produced by hydrolysis of 0.1 m FeCl 3 solution at 90°C. After 5 h of hydrolysis a pronounced decrease in particle size and the destruction of β-FeOOH morphologies, with an increase of urotropin concentration from 0.005 m to 0.25 m, were observed by XRD and TEM. The FT-IR spectra indicated that the bands at 833, 690 and 641 cm - 1 , typical of β-FeOOH, were strongly dependent on the changes in the structure of β-FeOOH caused by urotropin. After 7 days of hydrolysis, XRD and the FT-IR spectra showed that α-Fe 2 O 3 was the dominant reaction product for 0.1 m and α-FeOOH for 0.25 m urotropin, respectively. The nature of the observed effects is suggested.